1. Field of the Invention
The invention is directed to a coupling part for a fluid line coupling.
2. Description of the Related Art
One known coupling part is disclosed in DE 43 00 037 C1. The prior coupling part is provided with a locking element held in a receiving portion and designed to secure a plug-in part that is configured with an annular shoulder and is to be introduced into a receiving space of the receiving portion. The locking element is configured as an annularly closed spring element, in which two pressure plates emerging from the outer side of the receiving portion have two annular portions formed on them mutually oppositely, each annular portion being configured with a respective locking catch that engages behind the annular shoulder of the plug-in part. If the plug-in part is not inserted to the proper depth into the receiving space, however, there is a risk that the plug-in part will not be properly secured in the coupling part by the locking sections engaging behind the annular shoulder.
Known from DE 10 2004 062 887 B3 is a coupling part for a fluid line coupling in which a locking element is configured both with two retaining arms, which are devised to engage behind an annular shoulder configured on a plug-in part that is to be introduced into the coupling part, and with two locking arms. The locking arms are flexible in the axial direction of the coupling part, and each has at its free end an engaging arrangement that cooperates in such a way with a locking projection configured on the coupling element that when the plug-in part is introduced to the proper depth, the engagement between the engagement structure and the locking projection is released by the action of the annular shoulder butting against the locking arms and the locking arms flexing in the insertion direction, and the locking element can be shifted from an open position into a closed position that secures the plug-in part by virtue of the re-engagement of the locking structure and the locking projection. To release the connection between the plug-in part and the locking part, however, the locking arms must again be flexed in the insertion direction in order to release the engagement between the engagement structure and the locking projection in the closed position, a manipulation which, however, is very problematic or downright impossible, especially under very tight conditions.